The thermograph of the present invention is a recording thermometer that produces a thermogram for the protection of shippers and receivers of perishable goods by providing a permanent history of the temperature condition throughout the time interval of transit: reference being made to my co-pending application Ser. No. 253,202 filed May 15, 1972, entitled RECORDING THERMOMETER and issued Oct. 7, 1975 as U.S. Pat. No. 3,910,119. The present invention relates to improvements in such an instrument, namely in the compactness and durability thereof, and in the logic control and protection of a chart that is extracted in a cartridge; the loaded instrument being sealed in a shipping container with separate openable areas for purposeful access by the shipper and receiver, all as hereinafter described.
Recording temperature change is of the essence, a feature obviated by the concept disclosed in application Ser. No. 253,202 but with problems yet remaining with respect to compactness and durability. Namely, there is the necessity of reliance upon Postal Service for return of the instrument from the receivers, in order for the instrument to be reconditioned for use by subsequent shippers, and there is the severe punishment to which the instruments are subjected when in the return mail. Because of high and increasing postal rates, weight is a prime factor which dictates a light construction, preferably of 1 pound or less. And heretofore, corrugated cartons of multi-wall design have been employed for protection in the mails, but without complete success. Therefore, it is an object of this invention to retain light weight with heavier construction in a more compact embodiment, and it is also an object to provide an impact absorbent liner that supports the instrument per se within a box without resort to a multi-layer corrugated container. With the present invention, the idea of means resides in an instrument-liner-box concept; a sensible instrument that is pre-loaded and encased within a reuseable liner and sealed within an expendible box characterized by separately openable access doors. Instead of the mechanism being protectively carried entirely within a frame, the clock motor in particular is now carried at the exterior of the frame and within the liner, for its protection. Consequently, a frame of durable short coupled construction and of light weight becomes feasible.
Temperature isolation as a result of enclosure within a box or liner cannot be tolerated when the primary objective is timely response to temperature change. Therefore, it is an object of this invention to provide direct response to surrounding temperature despite the encasement by the insulating liner; there being a heat sink that is exposed to the surrounding environment through both the liner and enveloping box.
The instrument and shipping container concept of application Ser. No. 253,202 is characterized by a hinged top or cover that is opened and closed by both the shipper and the receiver, removal of pull pin used to initiate operation by the shipper, and by withdrawal of the chart and/or operation of a stop button used by the receiver to terminate operation; all features being exposed within one openable recess and inviting confusion by being accessible to both the shipper and receiver. It is an object, however, of the present invention to avoid confusion by providing separate and individual access to each person concerned, while the enclosure of the instrument remains intact. In other words, this instrument and liner remain enveloped within the box that is sealed thereover as a container, the box having one access opening for the exclusive employment by the shipper, and having another access opening for the exclusive employment by the receiver. With the present invention, each of said access openings is openable and resealable once with warranty, the features of the instrument as related to the shipper and receiver being exposed separately thereby.
It is an object of this invention to provide logic controls for an instrument of the character thus far referred to, with access by the shipper to record information (with copy) and to start the instrument and with access by the receiver to withdraw the record and to stop the instrument. With the present invention, there is a prepared chart accessible to the shipper through said one access opening exposing a start lever and directives for its operation, and there is the recorded chart accessability for the receiver through the said other access opening exposing a stop lever and directives for its operation. In accordance with this invention, I provide coordinated lever means associating the start and stop levers in the one instance to depress a stylus and release or energize a drive; and in the other instance to retract the stylus, stop or deenergize the drive and release the recorded chart for its extraction.
The preloading of a thermograph of the type under consideration normally results in stylus engagement against an immoveable chart during shelf-life of the instrument awaiting use. It has been found that this subjection is detrimental as it may cause a cut in the chart and subsequent tearing when the chart progresses. Therefore, it is an object to provide means for affecting the aforementioned depressing and lifting of the stylus, and all of which is coordinated with the starting and stopping of the instrument. With the present invention, an actuator is provided for predetermined positioning by the start and stop levers, the latter being reserved for release of the recorded chart, as will be described.
The extraction of the recorded chart presents problems that it is long and narrow and of frangible character. In practice, a spool partially draws up the recorded chart and it is an object of this invention to provide cartridge means facilitating completion of winding the chart onto the spool, prior to extraction thereof for inspection by the receiver.